AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Influence of Vapor Wall Loss in Laboratory Chambers on Secondary Organic Aerosol (SOA) Formation from Select Low Vapor Pressure-Volatile Organic Compounds (LVP-VOCs)
WEIHUA LI, Lijie Li, Mary Kacarab, David R. Cocker III, University of California, Riverside
Abstract Number: 252 Working Group: Aerosol Chemistry
Abstract A low vapor pressure-volatile organic compound (LVP-VOC) is defined by regulations as a chemical “compound” or “mixture” that has relatively low vapor pressure (0.01mm Hg) and high boiling point (>216°C). LVP-VOCs are essential components in consumer products used to meet product functionality and also volatile organic compound (VOC) limits. However, LVP-VOCs may still be present in the atmosphere through evaporation over extended periods of time contributing to VOC emissions and subsequently forming secondary organic aerosol (SOA) after photo-chemical oxidation. Therefore predicting the LVP-VOCs’ behavior in the atmosphere and their contribution to ambient fine particulate matter is important and contributes to our understanding of the poorly characterized and understood IVOC emissions and their role in SOA formation.
Teflon chambers are ubiquitous in the study of gas phase atmospheric chemistry and SOA formation from oxidation of VOCs. However, SOA formation can be significantly underestimated due to deposition of particles and SOA-forming vapors to chamber walls. Losses of particles to chamber walls are taken into account by current SOA formation models. However, there have only been a few studies evaluating the chamber surfaces in influencing lower vapor pressure VOC oxidation products availability for SOA formation. The goal of this study is to understand vapor wall loss effects on SOA forming-potential and growth from C$_(17)-C$_(23) alkanes as they partition between gas-phase, chamber surfaces, and particle surfaces. This study will provide a firm experimental foundation for evaluating current VOC exemption rules.